Battery Performance vs Temperature
Exponential temperature curves for LiPo battery efficiency
Optimal Temperature Range:
15°C to 25°C (59°F to 77°F)
LiPo batteries perform best within this temperature range, delivering maximum capacity and discharge rates.
Cold (< 0°C)
40-70% capacity
Reduced discharge rate, potential voltage drop under load
Cool (0-15°C)
70-90% capacity
Slight performance reduction, longer warm-up needed
Optimal (15-25°C)
95-100% capacity
Maximum performance, optimal discharge characteristics
Hot (> 35°C)
60-80% capacity
Risk of thermal runaway, permanent damage possible
Battery Efficiency Formula:
efficiency = exp(-((T - T_optimal) / 27)²)Where T is current temperature and T_optimal = 20°C
Air Density and Temperature
How temperature changes affect atmospheric conditions and flight performance
Air density decreases with increasing temperature according to the ideal gas law, directly impacting aircraft performance characteristics. (FAA Pilot's Handbook of Aeronautical Knowledge, Ch. 5)
Physical Principles
- Higher temperature correlates with lower air density
- Reduced air density results in decreased aerodynamic lift
- Propeller efficiency decreases in less dense air
- Increased power requirements for maintaining hover
- Higher battery discharge rates needed for equivalent performance
Performance Impact
- 10°C temperature increase produces approximately 3% density decrease
- Reduced flight duration in elevated temperature conditions
- Lower maximum altitude service ceiling
- Decreased payload carrying capacity
- Extended takeoff distance requirements
Air Density Formula (Ideal Gas Law):
ρ = (P × M) / (R × T)Where: ρ = density, P = pressure, M = molar mass, R = gas constant, T = absolute temperature
Electronic Component Considerations
Cold Weather Issues
- • LCD screens may freeze/slow
- • Capacitors lose effectiveness
- • IMU drift possible
- • GPS cold start delays
- • Servo response slower
Hot Weather Issues
- • CPU thermal throttling
- • Camera overheating
- • ESC temperature protection
- • Plastic components soften
- • Thermal expansion effects
Operating Ranges
- Storage: -10°C to 45°C
- Operation: 0°C to 40°C
- Charging: 5°C to 35°C
- Optimal: 15°C to 25°C
Temperature Lapse Rate
How temperature changes with altitude in the atmosphere
Standard Atmospheric Lapse Rate:
-6.5°C per 1000 meters (-2°C per 1000 feet)
This is the average rate at which temperature decreases with altitude in the troposphere under standard conditions.
Example Calculation
Ground temperature: 25°C
Flight altitude: 400 feet
Temperature drop: 400 × (-2/1000) = -0.8°C
Temperature at altitude: 24.2°C
Factors Affecting Lapse Rate
- • Humidity (wet vs dry adiabatic)
- • Time of day (thermal inversions)
- • Season and weather patterns
- • Geographic location
- • Local topography
Temperature Safety Guidelines
Cold Weather Precautions
- ✓ Keep batteries warm before flight
- ✓ Reduce initial flight time
- ✓ Monitor voltage more frequently
- ✓ Land earlier to preserve battery
- ✓ Store equipment in warm location
- ✓ Allow gradual temperature adjustment
Hot Weather Precautions
- ✓ Avoid direct sunlight on equipment
- ✓ Monitor component temperatures
- ✓ Reduce flight time in extreme heat
- ✓ Allow cooling time between flights
- ✓ Store in shaded, ventilated area
- ✓ Plan flights for cooler parts of day
Temperature Monitoring Tips
- • Use thermal imaging to check equipment temperature
- • Many modern drones report internal temperatures
- • Consider using temperature sensors for monitoring
- • Keep weather station or thermometer for ambient readings
- • Track temperature trends throughout flight session